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Gigantic Air Gun To Blast Cargo Into Orbit
Hugh Pickens writes: "The New Scientist reports that with a hat tip to Jules Verne's From the Earth to the Moon , physicist John Hunter has outlined the design of a gigantic gun that could slash the cost of putting cargo into orbit. At the Space Investment Summit in Boston last week, Hunter described the design for a 1.1-kilometer-long gun that he says could launch 450-kilogram payloads at 6 kilometers per second. A small rocket engine would then boost the projectile into low-Earth orbit. The gun would cost $500 million to build, says Hunter, but individual launch costs would be lower than current methods. 'We think it's at least a factor of 10 cheaper than anything else,' Hunter says. The gun is based on the SHARP (Super High Altitude Research Project) light gas gun Hunter helped to build in the 1990s while at the Lawrence Livermore National Laboratory (LLNL) in California. With a barrel 47 meters long, it used compressed hydrogen gas to fire projectiles weighing a few kilograms at speeds of up to 3 kilometers per second."
The real question on all of our minds though: "How far will it launch a pumpkin?"
Just wondering how they plan to address the problem of controlling the G-forces and prevent damages to the cargo.
The cannon idea was tried before ...... not a test single cargo survived the trip (or made it to orbit).
Is that a gigantic air gun with a 1km barrel in your classified launch facility, or are you just happy to see me?
~dijjnn
Gerald Bull was Canadian engineer who died (bullet in the head) trying to build such a cannon.
See http://en.wikipedia.org/wiki/Project_HARP
You can't take the sky from me...
I may be wrong in this calculation but running the numbers I get a weird result.
The gun is 1.1K long with a final velocity of 3km/s.
So the payload would be in the gun for 1.1/(3/2) = 0.73 seconds.
In that 0.73 seconds the payload would accelerate to 3 kms/sec The continuous acceleration would be 3000/9.8/0.73= 417 Gs. That is sure a lot of Gs. Much more than the 3.2 the shuttle produces.
Bullshit. Several weapon systems do just that, including the rocket assisted howitzer shells used in the M109 Paladin.
Search for Gerald Bull and read abut his super-gun project.
Only if you want them to arrive on orbit as people paste. The G-forces in a cannon launch would be very high.
I'll make a list...
Who ordered that?
> Cargo it seems would have a better chance but any sensitive equipment (like
> 99% of anything used in space) or explosive materials (fuel) wouldn't be able
> to be shot up in a gun.
Nonsense. Guns have been firing projectiles filled with explosives for centuries. The US Army has had shells filled not only with explosives but optics, electronics, and actuators for terminal guidance for dacades. In WWII they had anti-aircraft guns that fired shells with vacuum tube proximity detonators in them. In WWI they used shells with self-winding mechanical timers. Fuel would be easy.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Which, given that artillery shells exceed 2000g and are full of explosives, electronics, and machinery, should be easy.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
With discrete component electronics you just pot the whole thing in epoxy. I don't know how well that works with integrated circuits -- the point of failure is likely to be the fine wires that connect the chip to the package leads, although those may be light enough that the real concern is vibration rather than steady G force. Even vacuum tubes can be built tough, if they're built small.
But ~400 Gs (per calculations by a poster above) is nothing. The radio proximity fuzes in WW II antiaircraft projectiles didn't use transistors, and had to withstand ~20,000 Gs when fired and ~5,000 Gs of shell spin.
-- Alastair
He died in an earlier post.
Ah I love the smell of terrified redneck racist in the morning it smells like victory!
Still I pity your need to overcompensate for your inadequacies.
Matterafact, the proximity-fuzed antiaircraft shells of WW2 had a vacuum tube in them.
rj
Hey wait this guy might be on to something, this lattice reminds me of something.
"It's an energy field created by all living things. It surrounds us, penetrates us, and binds the galaxy together."
Yes that sounds similar!
We need to master the lattice and soon we will be able to jump really high, move shit with our minds, and battle each other with laser swords.
As a tax-payer, I refuse to fund it unless it makes a cool "FffffummmppPPP" sound.
Table-ized A.I.
You'll need conventional lift to get the tools up into space to build an orbital mining facility. This air-gun can be used to lift all the materials that those tools will use to build the mining facility and fuel for the crafts that will go get the asteroids and coax them back. But once that's done, we ought not need the air gun nearly as much or at all.
Depends on what you're planning, really. If your goal is to actually spread the human race out from Earth, this could be used long-term. Just keep sending up loads of water and compressed air, etc., for however long you can afford to do so. Keep the stuff in a stable orbit and just leave it there for however long you need (years, no problem, really). Once you're ready to use it (in LEO, at a Lagrange point, on the Moon, Mars, etc), move it to where you need it, as the most costly part of getting it into orbit has already been done.
That's one of the biggest problems with the U.S. space programs, the lack of long-term thinking and planning (and funding for a long-term strategy).
I've heard it argued by folks who sounded like they knew their stuff that it's much cheaper to do it by dragging in asteroids (maybe one with a cubic mile of ice in it) than to shoot it up from earth. I admit, I haven't seen the numbers.
Considering we just hit the Moon to try to figure out how much water ice is there, it seems unlikely that we have any good ideas on which asteroids have water ice in them, much less the ability to bring them to where we need them (yet). That's more the type of project I'd expect a few decades _after_ we do what this project is talking about. All in good time, my friend...
Since it would be used only for eco-friendly recycling, it could not possibly be considered a weapon of any sort.
I'm sure this is what medieval siege engineers shouted at the unhappy garrisons of besieged castles they were bombarding with decaying horse corpses: "That's no weapon, we're just recycling!"
Ezekiel 23:20